The subject invention relates to in general to vehicle brakes and, more specifically, to a method for producing a vehicle hub, bearing and brake disc assembly used in such a vehicle brake system.
With the advent of front wheel drive vehicles and disc brakes, the assembly which is driven by the drive shaft comprises a vehicle hub presenting a hub flange supporting a brake disc having opposed brake surfaces and with a bearing assembly surrounding the vehicle hub with an outer race presenting a bearing flange for attachment to a steering knuckle of a vehicle. When fully assembled on the vehicle, the brake surfaces of the disc rotor are disposed adjacent a pair of brake pads of a disc brake assembly and separated from engagement therewith by a normal brake running clearance when the disc brake assembly is not actuated. When the disc brake assembly is actuated, the brake pads take up the clearance and engage the brake surfaces of the brake disc.
In order to provide the normal brake running clearance, the brake disc must be manufactured to close tolerances with the brake surfaces oriented in a perpendicularly relationship relative to the axis of the brake disc and in parallel relationship relative to one another. A method of machining to close tolerances on a brake disc which is mounted through a bearing on a fixed stub shaft is disclosed in U.S. Pat. No. 5,430,926, to Dean J. Hartford. Normally, however, in a front drive or driven wheel a bearing assembly is disposed about the vehicle hub, rather than in the vehicle hub as in the aforementioned patent, and after the brake surfaces have been machined. As the assembly is mounted to the vehicle, the bearing assembly is loaded to finalize the relationship or orientation between the brake surfaces and the axis of rotation and can result in misalignment of the brake surfaces.